So I've had a vibration for some time. It starts at 65-70, gets bad by 80, and is REALLY bad by 90.

Get to 80, feel the vibration, push in the clutch and it gets worse.

I chased it for some time, unsuccessfully. Got a 4th gen aluminum driveshaft, had it balanced and new universal joints; no change.

New rear tires (they were shot); no change.

New front tires (they were shot, and flat-spotted); no change.

Just had the driveshaft rebalanced up to 6,000 rpm; no change

I was thinking it was the rearend, but the guy I took it to put it up on jackstands and ran it, and says he can hear a ton of bearing noise coming from the center of the transmission.

Wonder if the transmission is causing my vibration.

 

Have you checked for bent wheels or run out?

 

Yes.

Have balanced the tires both on, and off the car multiple times.

Have pulled the diff cover and inspected the rearend.

I got so disgusted with it I ended up parking the car for nearly 7 years.

I don't doubt it's the transmission, just wondering what could be wrong with the trans to cause a vibration like this.

 

I'm no expert on t5s,but if you have a failed bearing in the transmission,the output shaft can wobble and cause huge amount of runout of driveshaft-sounds like it is time to get the tranny down and apart for a look...Before that you could drain the tranny oil and look for failed bearing debris in the oil...

 

What kind of condition is the pilot bearing/bushing in?